proc new(M: type Mplex; conn: Connection;
         inTimeout: Duration = DefaultChanTimeout;
         outTimeout: Duration = DefaultChanTimeout;
         maxChannCount: int = MaxChannelCount): Mplex {....raises: [].}

proc newStreamInternal(m: Mplex; initiator: bool = true; chanId: uint64 = 0;
                       name: string = ""; timeout: Duration): LPChannel {.
    ...gcsafe, raises: [InvalidChannelIdError], raises: [],
    tags: [TimeEffect, RootEffect], forbids: [].}

func shortLog(m: Mplex): auto {....raises: [], tags: [], forbids: [].}

method close(m: Mplex): InternalRaisesFuture[void, void] {....stackTrace: false,
    raises: [], gcsafe, raises: [], tags: [RootEffect], forbids: [].}

method getStreams(m: Mplex): seq[Connection] {....gcsafe, raises: [], tags: [],
    forbids: [].}

method handle(m: Mplex): InternalRaisesFuture[void, void] {....stackTrace: false,
    raises: [], gcsafe, raises: [], tags: [RootEffect], forbids: [].}

method newStream(m: Mplex; name: string = ""; lazy: bool = false): InternalRaisesFuture[
    Connection, (CancelledError, LPStreamError, MuxerError)] {.
    ...stackTrace: false, raises: [], gcsafe, raises: [], tags: [RootEffect],
    forbids: [].}

template formatItIMPL(it: Mplex): auto {..}